Proflow's EFI fabricated intake manifolds are cost effective and performance filled! These Black Fabricated Intake manifolds feature 3mm (1/8 in.) thick 6061-T6 sheet aluminum construction with 100 percent TIG welds . The EFI versions have 92mm or 102mm throttle body openings, as well as runners with tapered tops to increase velocity and evenly distribute airflow. They also include fuel rail kits. These Proflow Intake Manifolds are avaliable in both LS1 /LS2/LS6 and LS3/L92.